A year after Prince proposed private troops for Nigeria, the West African nation is now using mercenaries. Prince’s old firm, Blackwater, used to contract with the U.S. to protect convoys and officials, and train foreign armies — but caused controversy when its employees killed Iraqi civilians.

The former defense contractors were charged with killing 14 Iraqi citizens and wounding 17 others in Baghdad in 2007. The incident caused an uproar about how private outfits working for the government operate in conflict zones.